A.20
Type	Water-cooled V12 engine
National origin	Italy
Manufacturer	FIAT
Major applications	Fiat CR.20 Macchi M.41

The Fiat A.20 was an Italian aero-engine of the 1920s. It was a water-cooled V12 engine that was used by early versions of the Fiat CR.20 fighter and the Macchi M.41 seaplane.

In 1923, FIAT built the A.15, a 430 hp (320 kW) water-cooled V12 engine. While no production of the A.15 ensued, it formed the basis for the Fiat A.20, which differed in being a Monobloc engine, and delivered a similar power despite a reduction in capacity from 20.3 to 18.7 L (1,239 to 1,141 in³).^[1]

Variants

A.20

Normal compression (5.7:1 compression)^[2]

A.20 S.

High compression version (6:1 compression)^[2]

A.20 AQ.

(AQ - Alta Quota - high altitude) High altitude version (8:1 compression)^[2]

Applications

• Ansaldo AC.4
• CANT 15
• CANT 25
• Fiat CR.20^[3]
• Macchi M.41^[4]
• Macchi M.71
• Piaggio P.6
• SIAI S.58bis
• SIAI S.67

Specifications (A.20)

Data from The Fiat A.20,^[5]Jane's all the World's Aircraft 1928.^[2]

General characteristics

• Type: Water-cooled 60° V-12
• Bore: 115 mm (4.53 in)
• Stroke: 150 mm (5.91 in)
• Displacement: 18.7 L (1,141 in³)^[6]
• Length: 1,645 mm (64.76 in)
• Width: 645 mm (25.39 in)
• Height: 845 mm (33.27 in)
• Dry weight: 340 kg (749.6 lb)

Components

• Valvetrain: Overhead camshafts operating two inlet and two exhaust valves per cylinder via rockers
• Fuel system: Two twin carburettors
• Cooling system: water-cooled

Performance

• Power output: **A.20 460 hp (343.0 kW) at 2,300 rpm
  • A.20S 510 hp (380.3 kW) at 2,400 rpm
  • A.20AQ 430 hp (320.7 kW) at 2,060 rpm maximum continuous; 540 hp (402.7 kW) at 2,400 rpm maximum momentary output
• Compression ratio: **A.20 5.7:1
  • A.20S 6:1
  • A.20AQ 8:1
• Specific fuel consumption: 0.528 lb/(hp⋅h) (0.321 kg/kWh)